Single/multi-objective optimization and comparative analysis of liquid-metal heat pipe

Heat pipes utilize the latent heat of vaporization and lie on the capillary forces to maintain the circulation of working fluid. High-temperature heat pipes applied in the nuclear silent thermal-electrical reactor are investigated and optimized. Nine wick structures and several design variables are investigated in the single/multi-objective optimization. The improved network thermodynamic model of a heat pipe is adopted, and the thermal resistance, mass, and transport capacity of wicks are selected as the objective functions. Multi-objective optimization results are obtained by Pareto-optimal points. Comparative results reveal that mesh screen and annular artery present a better performance (0.00180 K/W) in both single and multiple objective optimizations. Potassium is preferred for the wick of the circular artery and rectangular artery, while sodium is preferred for the wick of isosceles-triangular groove and sintered fibers. And with the operating temperature (800 similar to 950 K), thermal resistance is decreased with the simultaneous rise of mass (165.2%) and transport capacity (154.6%) in the mesh screen. This work makes it possible to improve the operational performance of a heat pipe and provides a reference for the selection of wick structure and heat pipe design.

Automated summary

This study investigates and optimizes high-temperature heat pipes, providing important insights through multi-objective optimization. The results reveal that mesh screen and annular artery perform better, different wick materials have different effects on the performance of different wick structures, and as the temperature increases within the specified range, the thermal resistance decreases while the mass and transport capacity increase.